The removal of unwanted and/or life threatening biological material from interior portions of bodily cavities, such as organs, vessels, articular joints and structures, sinuses, and various bodily lumens, is a very common procedure in various medical specialties and disciplines, such as pulmonology, cardiology, urology, gynecology, gastro-enterology, neurology, otolaryngology, orthopedics, and general surgery. Accordingly, various instruments and methods have been employed to perform these procedures, which are generally well known in the art.
One of the most important complications in such procedures is bleeding. The bleeding and resulting morbidity of tissue that occurs in many of the currently known surgical procedures is the result of abrasive, traumatic, and invasive excising and removal techniques. Many of these techniques risk perforation of the vessel or lumen in which the procedure is being performed, resulting in grave complications for the surgeon and patient. In addition, many patient maladies are simply not remedied by these procedures because no interventional, minimally invasive treatment modality exists, the methods are not efficient, safe, and reproducible, and/or the instruments employed lack the appropriate visualization, physiological measurement, and/or feedback necessary to ensure the safety, efficacy, and reproducibility of the procedure. Accordingly, a new type of treatment is required.
One instrument that is commonly used in various types of medical procedures is an inflatable balloon catheter, of which many different types exist, which are utilized to perform various necessary functions. For example, these inflatable balloons are often used to control or stop bleeding, to hold instruments in place, or to prevent or facilitate other flow or movement within the bodily cavity. For example, many urological catheters are held in place via a balloon that impacts the sidewalls of the urinary tract, many gynecological instruments are held in place via balloons that impact the sidewalls of the vaginal vault, endovascular balloons are often used to control bleeding, inflatable balloons are sometimes used to control the backflow of radio-opaque agents injected into the cystic duct to detect the presence of gall stones during general surgical cholecystectomy procedures, and, recently, balloon catheters have been employed to release sinus congestion.
One particular application of such catheters is lung cancer. Among all types of cancer, this has the lowest survival rate, as more than one third of all deaths due to cancer are caused by lung cancer. Over 1.5 million new cases are diagnosed worldwide each year. The most frequent cause of death for lung cancer patients is airway obstruction. In lung cancer patients, one third of all cases initially, and another third of the cases in the long term, present main airway obstruction, which may cause asphyxia, hemorrhaging, and infection. These complications are the most frequent causes of death in lung cancer patients.
Use of interventional bronchoscopy for the treatment of lung cancer and the resultant airway obstruction increases the quality of life and survival rates of patients suffering from Chronic Obstructive Pulmonary Disease (COPD) and the obstructive co-morbidities associated with the cancer. Accordingly, balloon catheters have been routinely used with various endoscopes and with flexible and rigid bronchoscopes for dilation, as a tamponade to stop bleeding, and as an interference fixation device to hold instruments in place and prevent the retropulsion of those instruments under backflow pressure.
In light of the aforementioned need for a new type of treatment for removing undesirable biological material in bodily cavities, it has been realized that inflatable balloon catheters may further be employed as interventional tools for the excision and removal of such materials—such as endoluminal obstructions and tumors and endovascular occlusions—in various applications, such as the aforementioned interventional medical specialties of pulmonology, cardiology, urology, gynecology, gastro-enterology, neurology, otolaryngology, and general surgery. The use of balloon catheters in this way has presented a method of treatment that is simple, safe, highly effective, and inexpensive compared to other types of methods and devices that are used, such as mechanical, laser, electrocautery, cryotherapy, etc.
Accordingly, a new class of balloons has been suggested for this purpose, such as that disclosed in U.S. Pat. No. 8,226,601 to Gunday et al., the specification of which is hereby incorporated by reference herein in its entirety. This device employs a balloon catheter with an inflatable resector balloon. Using this device, one is able to treat obstruction in a bodily cavity by inserting the catheter with the balloon deflated into the bodily cavity. The balloon is aligned with the obstruction and then repeatedly inflated and deflated in pulsed fashion. The balloon's abrasive surface, when gradually pulsed in this way, gradually and non-traumatically resects the obstruction, while causing minimal damage to the surrounding, healthy tissue.
While this system is of great use for safely removing undesirable biological materials from bodily cavities, there is a need to also provide a system that does not rely on separate control units to operate the resection system. For example, prior systems may employ an electro-pneumatic pump, which is very accurate and convenient. However, such a device may need to be mounted on a rack or boom arm with other self-contained units, such as camera control units, insufflators, and electrosurgical units, not within the surgeon's reach, such that the surgeon will need to move away from the operating table or rely on assistants in order to make adjustments. Moreover, many medical practitioners prefer to be able to directly and actively control the operation of the devices they are using to perform the procedure, rather than relying on a device to control them automatically based on previously entered parameters.
In addition, the resector balloon catheter must be inserted into a narrow and vital body cavity, such as a respiratory airway or coronary artery, and the doctor must conduct a precise procedure using the inserted device. Accordingly, it is desirable to have imaging available to provide the doctors with a view that facilitates precise positioning and operation of the device. Such imaging systems typically comprise some kind of manually manipulated scope, connected to a camera control unit for receiving and processing the optical signals that, as referenced above, is typically a self-contained unit located on a rack or boom arm. A separate imaging system such as this can be difficult to hold and manipulate while one is also holding and operating a handheld balloon catheter and pump.
Also, the interior of the human body is almost completely dark, and proper illumination of the target site inside the body is required in order to obtain useful images. Specifically, light must be delivered to the interior body, into the field of view of the imaging device, such that the reflected light can be captured and transmitted to an appropriate device for rendering those images.
In traditional operating environments, light is transmitted from an external light source into the patient. Since these light sources must be very bright in order to provide sufficient illumination for imaging, they tend to generate significant heat. Since they generate so much heat, which could damage any biological tissue with which they come into contact, it is common to use self-contained, external light sources. A typical example of this is described in U.S. Pat. Nos. 7,668,450 and 8,246,230 to Todd et al. As described therein, a typical light source unit includes a light bulb, a ballast power supply, controls, and cooling fans. These light source units are, like the electro-pneumatic pump and camera control unit discussed above, typically mounted on a rack or boom arm along with other devices. The light generated by this light source in supplied through a light guide, such as a fiber optic cable, which transmits the light to the instrument being used in the patient.
These light sources, which require a lot of space and power, have a number of disadvantages. First, they are inefficient, as they must generate extremely intense light in order to compensate for the distance the light must travel along the cable from the unit to the instrument. Additionally, they can create dangerous conditions by transmitting heat energy to the patient. Further, the light cable is both cumbersome and further adds to the hazard of having too many cables in an already crowded room that can trip the medical professional or supporting personnel.
Accordingly, it has been proposed to instead use LEDs as a source of illumination. Because they are so small, they can be integrated into the imaging device, much closer to the target site, and their high light output, low cost, longevity, and reliability make them a desirable solution.
However, LED based light sources can get very hot during operation, and thus, can cause burns and equipment damage due to these high operating temperatures. These problems are very prominent when the light source is integrated in a portable or handheld medical device, which the LED will heat up. This can be hazardous for the patient, who will be in direct contact with the hot imaging device or instrument housing the LED, or possibly the hot LED itself, which can result in burns. Likewise, the medical practitioner holding the medical device can likewise be burned, resulting in injury to the practitioner, as well as serious injury to the patient if the practitioner unexpectedly moves or drops the instrument as a result. Additionally, heat can damage the device housing the LED, such as the optical elements of the imaging device.
Moreover, in addition to facilitating insertion of an imaging device, fluid must be continually supplied and withdrawn from the resecting balloon in order for it to function, and it is also desirable to deliver diagnostic and/or therapeutic agents to the target site to help diagnose and treat the pathology. All of these features, of course, add to the complexity of the resection system. In order to accommodate them, the catheter must have multiple lumens. Furthermore, the catheter must remain as slim as possible to be able to enter narrow passages in the body. Finally, all of these devices and components (i.e., optics, pressurized fluid for the balloon, drugs) must be fed into the various lumens of the catheter from outside of the patient's body.
What is desired, therefore, is a resector balloon system for removing undesirable biological materials that repeatedly inflates and deflates the balloon in pulsed fashion to resect the biological material that a medical practitioner can hold and actively control while performing the procedure. What is also desired is a resector balloon system that is able to facilitate precise positioning and operation of that device. What is further desired is an assembly that is able to facilitate diagnosis and/or additional treatment steps during the resection procedure with a small and efficient assembly.